A PATH FOR A PACKAGING BELT

Abstract: The invention relates to a path (3) for positioning a continuously flexible packaging belt (20) which displays two opposing walls (21a, b) defining packaging blanks (26) disposed mutually after one another in the longitudinal direction of the path and each one provided with a closed bottom portion in the first edge (22) of the belt and opposing edge portions (24a, b) at the other edge (23) of the belt. The path includes mechanical guide members (33a, b) provided with at least one channel (31a, b) for guiding the edge portions (24a, b) on displacement of the belt into an apparatus for the infeed of contents into the packaging blanks (26). The mechanical guide members (33a, b) are formed from a number of links (30). In the part or parts where the edge portions (24a, b) of the belt are to be kept a distance from one another, the links are disposed in mutual spaced-apart relationship.

Description: A PATH FOR A PACKAGING BELT The present invention relates to a path for positioning a continuously flexible packaging web according to the preamble of the independent claim. There are needs in the art for a mechanical path for positioning a continuously flexible packaging web, comprising a number of mutually ubsequently disposed packaging blanks each one with a closed bottom portion, in which, on positioning, edge portions of the web are posi¬ tioned a distance from one another in order to open the packaging blanks and thereby make them accessible for the supply of contents. EP-B1-0 054564 discloses a path of the above type. The path includes guide members designed as rods along which a flexible packaging web is displaced. The guide rods are of a predetermined shape which is adapted to the size of the packaging blanks. When the dimensions of the open¬ ings of the packaging blanks are changed, rods included in the path are replaced by rods adapted to the new dimensions. The need for this ex¬ change of rods reduces the flexibility of the path. The present invention discloses a path which, on changed dimensions of the openings of the packaging blanks, can be switched so as to adapt the distance between retainer devices for the edge portions of the packaging web to suit the size of the openings of the packaging blanks. This is attained using a technique as disclosed in the characterizing clause of the independent claim. Expedient embodiments of the present invention are disclosed in the appended subclaims. The present invention will now be described in greater detail hereinbelow, with reference to a number of Figures, in which: Fig. 1 is a perspective view of a portion of a packaging web; Fig. 2 shows the cross-section 11-11 in Fig. 1; Fig. 3a,b show portions of a first embodiment of the path in the region of the opening of packaging blanks, where the path is composed of links disposed after one another; Fig. 4a,b are cross-sections of mechanical guide members for guiding the packaging web where Fig. 4b also shows the upper portion of the packaging web; Fig. 5a shows a second embodiment of the path corresponding to the section A-A in Fig. 5b, where the path is provided with a mechanically stable guide member for opening a packaging blank; Fig. 5b shows the path of Fig. 5a seen from above; Fig. 5c is the section C-C in Fig. 5a; Fig. 6a shows a third embodiment of the path seen from above and provided with a mechanically stable guide member and with an alternative version of the links included in the path; Fig. 6b shows the section B-B in Fig. 6a; Fig. 7a shows a fourth embodiment of the path seen from above; and Fig. 7b shows the path according to Fig. 7a seen from the side. Figs. 1 and 2 show one embodiment of a continuous packaging web 20 of flexible material which displays two opposing walls 21a,b and longi¬ tudinal first and second edges 22 and 23, respectively. The belt includes a number of mutually subsequently disposed packaging blanks or pockets 26. The pockets each have a bottom portion at said first edge 22, and two connection zones or joints 25, occasionally designated transverse zones 25, which are transversally directed in relation to the longitudinal direction of the belt and which form the side closures 25 of the pockets. In Figs. 1 and 2, the belt is shown with a folded-in bottom. The upstanding definition of the folded-in bottom has reference numeral 47 and corresponds to a centre line of a belt which has been folded together on the formation of the packaging belt. Between the joints of two adjacent pockets or bags there is a transverse slot 27 which defines the pockets from one another. In certain embodiments, mutually adjacent pockets 26 are united by means of one or more bridges 75. In this instance, such bridges are as a rule disposed in the vicin¬ ity of the first edge 22 of the belt. Each respective wall 21a,b includes two opposing edge portions 24a,b which extend in the longitudinal direction of the belt at its said second edge 23, each one including a continuously retained member generally designed as a material thickening, 43a,b for cooperation with mechanical members 33a,b (cf. Fig. 3) for guiding the edge portions 24a,b on displacement of ttie belt 20 into an apparatus 3 for feeding contents into the pockets 26. In the illustrated embodiment, a longitudinal slot 29 is provided on either side of each transverse slot 27. The longitudinal slot is located between the retainer members 43a,b and the pockets 26. Two mutually adjacent longitudinal slots are thus located in spaced apart relationship from one another in the longitudinal direction of the belt. Each one of the edge portions 24a,b includes a strap-like portion 14a,b which forms the other edge 23 of the belt. The strap-like portion 14a,b merges into the retainer members 43a,b in the direction towards the pockets 26. The connections of the straps to the retainer members 43a,b carry reference numerals 73a,b. In Figs. 3a and 3b, as well as Figs. 4a and 4b, there is shown one embodiment of a path 3 comprising a number of mutually subsequently disposed links 30. A transition 32 is formed between two mutually subsequent links, in which transition there is disposed a mechanical shaft 37 arranged at right angles to the longitudinal directions of the links. The shaft 37 is located between the end surfaces 38 of the links. These are in turn located a short distance from one another so that the links are, to a limited extent, rotary in relation to one another about the mechanical shafts 37. The end surfaces are as a rule disposed at an oblique angle to the longitudinal direction of the links and are generally substantially planar. In practical applications where particularly powerful changes in direction are required in the transi¬ tions 32, they are given a slightly rounded shape. At the same time, the links are made relatively short. The links include a channel 31a,b in which the thickened portions 43a,b of the packaging belt 20 are displaced in the direction- of the arrows A. In the right and left-hand portions of the Figures, the links are in lateral abutment against one another while, in the central portions of the Figures, the links 30 are parted so that a gap exists between them. The transitions between those parts of the path where the links are located adjacent one another and that part of the path where the links are parted carries reference numeral 40. Fig. 4a shows the cross-section through one embodiment of the links 30a,b where the links have through gap 34a,b downwardly directed in the Figure. The width of the gap is selected so that the thickened portions 43a,b of the packaging belt cannot pass through the gaps. In Fig. 4b, driving belts 46a,b are also shown, these generally being designed as cogged belts. The driving belts press both walls 21a,b of the packaging belt between themselves and thereby the walls against one another in the edge regions 24a,b of the packaging belt and thereby displace, on their movement, the packaging belt in the longitudinal direction of the channels 31a,b. In the cut-out portion of Fig. 3a, there are shown, in addition to the channel 31a and the wall 21a of the packaging belt, longitudinal elas¬ tic means, e.g. springs 36 which, in the extended state, are secured to retainer devices 39. The springs are disposed so that they pass the transition 32 between two mutually subsequently disposed links 30. Each spring is thus secured at retainer devices 39 disposed in two different links. The channels 31a,b in the links 30a,b discharge in the end sur¬ faces 38 of the links on the opposite side of the mechanical shafts 37 and substantially in register with the openings of the channels 31a,b of following links. Hereby, the channels of the links 30 form a sub¬ stantially continuous guide member for positioning the thickened por- tions 43a,b of the packaging belt 20. In Fig. 3a, the distance between the mutually parted links is greater than in Fig. 3b. The difference in distance is determined by the dis¬ tance between the transitions 40 where the links 30a,b are directed from one another and where the links 30a,b once again connect to links 30 in abutment against one another, respectively. In order to regulate this distance, the size of the opening 35a,b between mutually subse¬ quently located and laterally mutually abutting links is lockably adjustable for one or more transitions 32 adjacent the parted links. This is clearly shown in Figs. 3a,b by the arrow B. In the upper Figure, the distance between the transitions 40 is less than in the lower Figure. The springs 36 strive to turn adjacent links so that their opposing end surfaces 38 reach contact with one another, but this turning movement is prevented by the fact that the positions of the transitions 40 are fixed. The described construction of the path entails that the opening 35 which is formed between the parted links is single and continuously adjustable for adaptation to the size of the packaging blanks which are included in the packaging belt. Locking of the adjusted size of the opening 35 is obtained by fixing the mutually adjacent links 30 in relation to one another and thereby the distance B determining the size of the opening 35. It is obvious that a corresponding function is achieved if the springs 36 and the channels 31 change place in relation to the mechanical shaft 37. Figs. 5a and 5b as well as Figs. 6a and 6b show one embodiment of the path where an opening 52 corresponding to the previously described opening 35 between parted links is formed by a mechanically stable device 50. This device has an edge portion 53 disposed in the circum- ferential direction of the opening 52 and accommodating channels 51a,b which discharge in regions 55 in association with the regions 45 adjacent which discharge channels 31a,b cooperating with the device 50 or alternatively a common channel 31 for the links. In the embodiment shown in the Figures, the edge portion 53 is composed of an inner por¬ tion 53a and an outer portion 53b between which parts the channels 51a,b are disposed. Also in this embodiment, the channels are acces- ■ sible through a gap 54 which is formed between both parts. The width of the gap is less than the thickness of the thickened portions 43a,b of the packaging belts. All of the above described embodiments of the path 3 are intended for handling and filling a packaging belt 20 witn the slots 29a,b disposed in the longitudinal direction of the belt and described with reference to Figs. 1 and 2. Occasionally, packaging belts are, however, demanded which do not feature these slots. One embodiment of the present inven- tion will be described hereinbelow with reference to Figs. 7a and 7b in which the path 3 is disposed to be displaced and make possible filling of packaging blanks included in the packaging belt but in which the packaging belt has no longitudinal slots for facilitating opening of the packaging blanks. Figs 7a and 7b show a path 3 where the opening 35 between parted links is formed by four part links 30' which are displaceable between posi¬ tions in which the links 30 are parallel with one another and abut against one another, and positions in which the links pairwise make an angle with one another. The links are journalled at the mechanical shafts 37 for connection to surrounding links 30 corresponding to that described above. In the direction of transport of the path, two links 30 , 30 ' which precede or follow on the links which make the opening are displacebly disposed in relation to one another. Between the end surfaces 38 , 38" " of the links the distance is variable from no dis¬ tance to a distance corresponding to that distance which entails maximum angle between the pairwise disposed links 30'. For displacement of the mutually shiftable links 30", 30" ' there is provided a drive member 60, as a rule a hydraulic unit, comprising a cylinder 61 and a piston (ram) 62. The drive member is provided with anchorage means 63, 64 which are interconnected with fixing members 47, 48 provided on the links 30", 30" ' . The links or the drive member are lockable in the set position. Fig. 7a also shows how links with obliquely inclined end surfaces 38 are connected to one another so as to form a curved conveyor path. When using the path 3 illustrated in Figs. 3-4, the packaging belt 20 is continually or intermittently drawn in the direction of the arrows A by means of the driving belts 46a,b. Both opposing edge portions 24a,b of the packaging belt 20 are here positioned by the channels 31a,b and the gaps 34a,b of the mechanical guide members 33a,b. The gaps prevent the material thickened portions 43a,b of the belt from leaving the channels when the thickened portions of the belt are displaced in the longitudinal direction of the channels. When the belt passes a transi- tion 40 for the first time, the mechanical guide members 33a,b displace the edge portions 24a,b of the belt away from one another, and when the belt reaches the next transition 40, the mechanical guide members re¬ turn the edge portions 24a,b of the belts to positions adjacent one another. The packaging blank or blanks which are located in the region between the two transitions 40 are thereby held open by the mechanical guide members and are accessible for the infeed of contents. The mechanical guide members 33a,b set the maximum distance between the edge portions 24a,b at a size which is dependent upon the adjustments of the conveyor path which had been carried out previously in view of the length of the slots 29 of the packaging belt. The distance between the mechanical guide members 33a,b which are loca- ted between said transitions 40 is adjusted by means of the link 30 by displacement thereof in the direction of the double arrow C (cf. Fig. 3a). On the displacement of the link 30, the distance B between the link 30 and an adjacent link 30 is altered. In such instance, the dis¬ tance between the belt transitions 40 in which the mechanical guide members 33a,b displace the edge portions of the belt away from or to¬ wards one another is also altered. In Fig. 3b, the distance is slight in the transition 32 between the two adjacent links 30, and the dis¬ tance is large between the transitions 40 in which the mechanical guide members 33a,b displace the edge portions of the belt away from or to one another. The distance between the mechanical guide members 33a,b in the region between the previously mentioned transitions 40 is thereby slight. On switching of the distance, the links are rotated about the mechani- cal shafts 37 in the transitions 32 between the links for those links which are located at the transition 40 or in the region between the transitions 40. The springs 36 strive to move the end surfaces 38 of the links into abutment against one another in those areas of the end surfaces which are located on the same side of the mechanical shafts 37 as the springs 36. The rotational position to which the links are set is determined by the positions of the links 30 to which the mechanical guide members 33a,b merge into the transitions 40. When the embodiments illustrated in Figs. 5 and 6 are put into use, the packaging belt 20 is displaced by drive means (not shown in the draw¬ ings) in the direction of the arrows A. The opposing edge portions 24a,b of the packaging belt are displaced in the longitudinal direction of the channels corresponding to that described in connection with Figs. 3 and 4, at the same time as a packaging blank 26 which is posi¬ tioned in the channels 51a,b of the mechanically stable guide member 50 is kept open for the infeed of contents through the opening 52 of the mechanically stable guide member 50. Since the mechanically stable guide member 50 has a determined shape, no devices are necessary here for altering the distance between the links 30 and the mechanically stable guide member. As a rule, the embodiment of the links 30 illus- trated in Fig. 6b is chosen, according to which the links are formed from two part links 30a, 30b which, therebetween, form the channel 31 and the through gap 34. On employment of the path illustrated in Figs. 7a and 7b, which is particularly suitable for handling packaging belts 20 with packaging blanks 26 which lack the horizontal slot 29, the belt 20 is moved through the channels 31 by means of displacement devices (not shown). In the starting position, the separable links 30' are located in positions adjacent one another. When a packaging blank 26, with the links 30 abutting against one another, assumes the position in which the central portions of the blank are located in the region of the transitions 32 between the links 30' which may be displaced pairwise between positions in which they abut against one another and pairwise make an angle with one another, the drive means 60 displace the links 30 , 30" from one another whereby the distance between the transitions 40 is reduced and the links 30' are rotated outwardly from their posi¬ tions adjacent one another. In this instance, the packaging blank 26. is opened and will be accessible for the infeed of contents. The length of the channel 31 of these two links which are located between the tran- sitions 40 is the same irrespective of the position assumed by the links. Hereby, the need for slots to open the packaging blanks 26 will be eliminated. It will also be apparent from Fig. 7a that the path is given a curved configuration by providing one or more links with end surfaces 38 which make an acute angle with one another. In other practical applications of the invention, use is made, in straight sections of the path, of links 30 which have mutually parallel end surfaces 38 which are located at an oblique angle to the longitudinal direction of the links. Cf. the angled links 30 shown in Fig. 3a most proximal to the transitions 40. In the above description, use has occasionally been made of the desig¬ nations upper, lower, right, left etc. These designations have been employed to facilitate presentation of the invention. It is obvious to a person skilled in the art that the described technique generally permits an optional spatial orientation of the path. The above detailed description has referred to but a limited number of embodiments of the present invention, but a person skilled in the art will readily perceive that the present invention accommodates a large number of embodiments without departing from the spirit and scope of the appended claims.

Claims: CLAIMS 1. A path (3) for positioning a continuously flexible packaging belt (20) which displays two opposing walls (21a,b) and longitudinal first and second edges (22, 23), the belt (20) including packaging blanks (26) disposed after one another in the longitudinal direc¬ tion of the path and each with a closed bottom portion at the first edge (22) of the belt, and two opposing edge portions (24a,b) at- the other edge (23) of the belt, the edge portions (24a,b) extend¬ ing in the longitudinal direction of the belt (20) and being provided with longitudinal thickened portions (43a,b) where said edge portions (24a,b) are movable relative to one another in the transverse direction of the belt (20), said path including mechani- cal guide members (33a,b; 50) provided with at least one channel (31; 31a,b; 51a,b) for guiding the edge portions (24a,b) on dis¬ placement of the belt in an apparatus (20) for feeding contents into the packaging blanks (26), c h a r a c t e r i z e d i n t h a t said mechanical members (33a,b) include at least one channel (31; 31a,b; 51a,b) formed in a number of links (30) inclu¬ ded in the path and/or formed in an edge region (53) of a mechani¬ cally stable member (50) with a through opening (52) located inside its edge region (53); and that in the part or parts where the edge portions (24a,b) of the belt are to be kept spaced apart from one another by the links (30a,b respectively) these are disposed in spaced apart relationship from one another. 2. The path as claimed in claim 1, c h a r a c t e r i z e d i n t h a t the bounding " definition of said channel (31; 31a,b; 51a,b) is provided with a through gap (34) whose minimum width is less than the width of the thickened material portions (43a,b). 3. The path as claimed in claim 1 or 2, c h a r a c t e r i z e d i n t h a t there are disposed between mutually subsequent links (30) mechanical shafts (37) which are oriented at right angles to the longitudinal directions of the links (30); and that mutually adjacent links (30) are rotatable, at least limitedly, about said shafts (37). 4. The path as claimed in any one of claims 1 to 3, c h a r a c - t e r i z e d i n t h a t in a transition (32) between two mutually adjacent links (30), the end surfaces (38) of the links are substantially parallel with one another; and that, at least in the transition (32) where the mechanical guide members (33a,b) al¬ ter the direction of the belt, said end surfaces (38) make an oblique angle with the longitudinal direction of each respective link (30). 5. The path as claimed in any one of claims 1 to 4, c h a r a c ¬ t e r i z e d i n t h a t an elastically resilient device (36) is pretensioned in the extended state between retainer members (39) in two mutually subsequent links (30). 6. The path as claimed in any one of claims 1 to 5, c h a r a c ¬ t e r i z e d i n t h a t said channel (31) is, in each link (30), disposed such that its opening (35) in the end surface (38) of the link is located adjacent the shaft (37). 7. The path as claimed in claim 5 or 6, c h a r a c t e r i z e d i n t h a t in each transition (32) between two mutually subse- quently disposed links, the openings (35) of the channels (31) and the resiliently yieldable device (36) are disposed on each side of the shaft (37). 8. The path as claimed in any one of claims l to 7, c h a r a c - t e r i z e d i n t h a t the distance between one transition (40) in which the mechanical guide members (33a,b) displace the edge portions (24a,b) of the belt away from one another and a sub¬ sequent transition in which the mechanical guide members (33a,b) displace the edge portions (24a,b) to positions adjacent one an- other is regulatable for adjusting the distance between the mecha¬ nical guide members (33a,b) in the region between said transitions (40).

Inventors: BRODEN INGEMAR, JOSTLER JAN, BRODEN, INGEMAR, JOSTLER, JAN
Applicants: BRODEN INGEMAR, JOSTLER JAN, BRODEN, INGEMAR, JOSTLER, JAN
Application year: 1994
Main classification: B65B43
IPC codes: B65B43, B65D33